Clamp for button-hole sewing-machines



(Nomodelj) E. B. ALLEN.

GLAMP POB, BUTTON HOLE SEWING MAGHINBS.

No. 439,087. Patented Oct. 28, 1890.

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UNITED STATES PATENT OFFICE.

EDWARD B. ALLEN, OF PORTLAND, MAINE, ASSIGNOR TO THE SINGER MANUFACTURING COMPANY, OF NEW JERSEY.

CLAMP FOR BUTTON-HOLE SEWING-MACHINES.

SPECIFICATION forming part of Letters Patent No. 439,07, dated October 28, 1890.

Application filed January 9, 1890. Serial No. 336,334. (No model.)

To all whom t may concern:

Be it known that I, EDWARD B. ALLEN, of

Portland, county of Cumberland, State of Maine, have invented an Improvement in Clamps for Button-Hole Work, of which the following description, in connection with the accompanying drawings, is a specification, like letters and iigures on the drawings representing like parts.

The material, leather or cloth, to have button-holes overstitched therein is now commonly held in a clamp, which is moved under the needle of the stitch-forming mechanism, and this clamp in many machines has a sliding movement and a partial rotation. When the stitching for a button-hole has been finished, the machine is stopped and the operator breaks or cuts the needle-thread near the clamp and holds the broken end, and with his other hand on the needle-thread at the other side of the needle he draws from the tension device a sufficient quantity of thread and pulls it through the eye of the needle to thus have sufficient thread to start the button-hole next to be stitched. In doing this the operator commonlyT draws from the tension device much more thread-usually silk, and expensive--than is needed to start the next button-hole, and in practice very much silk is wasted, the waste being estimated as high as seven per cent. To obviate this waste of silk, and to also economize time,

' I have provided a cloth-clamp with a thread clamp or jaw, and also with a cutter to automatically sever the needle-thread close to the finished end of the button-hole, the threadclamp holding the said thread while the material is changed in the cloth-clamp, the said thread-clamp holding the end of the said thread at the proper side of the eye of the needle until aft-er the stitching for another button-hole has been commenced.

Believing myself to be the iirst to devise means-to hold and cut the needle-thread between the material held in the cloth-clamp and the needle, I desire it to be understood that I do not intend to limit my invention to the particular thread-clamp shown or to the particular cutter shown, nor do I desire to limit my invention to the application of a thread clamp and cutter or to the' particular form of cloth-clamp herein shown.

One feature of my invention thereforeconsists in a cloth-clamp and a -traveling co-operating thread-clamp to seize and clamp the needle-thread between the material in the cloth-clamp and the eye of the needle after the completion of the stitching for a buttonhole and before the material is removed from the clamp.

Another feature of myinvention consists in the combination, with a cloth-clamp and a thread-clamp to hold the needle-thread bewill become apparent in the following description and claims at the end thereof.

Figure l is a top or plan view of one wellknown form of cloth-clamp with my improvements added thereto, the parts being in the position they will occupy when the machine isto be started to stitch a button-hole in material held in usual manner in the clothclamp. Fig. 2 is a partial side elevation thereof, showing part of the usual eye-pointed needle with the thread extended therefrom to the thread-clamp, the upper jaws of the clothclamp and the parts for supporting and moving them being omitted. Fig. 3 is a detail with the cap shown in Figs. 1 and 2 removed, the said figures also showing a piece of material with a slit cut therein for a button-hole next to be overstitched. Fig. 4 is a detail with the slide of Fig. 3 removed to show the thread-cutter under it. Fig. 5 is an elevation from the left of Fig. 2, the needle being omitted; and Figs. 6 and 7 are details to be referred to.

The base a of the cloth-clamp, the laterally-movable jaws d', on which the material to be stitched rests, the lever a2, to move the said jaws away from each other to expand the slit s2 ofthe material s3, the arms a3, connected by screws a5 to the blocks a4, having their fulcra on studs a6 in ears a7, connected to the rear ends of the jaws a', part of one of the said ears being brokenoff in Fig.'2, the

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rack-shaft b, having an attached lever b' at 011e end and provided between its ends with a crank, which is embraced in usual manner by a link b2, surrounding at its upper end a yoke b3, which connects the arms a3, the wedge-blocks b4, attached to the arms afs by screws b5, the arms a3 being normally kept elevated by springs under them, the top jaws b of the cloth-clamp, pivoted on the arms a3, the stand 57, forming a rigid part of the base a, and bored to receive the vertical pin bs, which in practice enters a slot in the bedpiece of the machine and then a groove in a cam under the bed-piece, and the springao, to normally keep the said pin depressed, are or may be all as usual in cloth-clamps, the particular cloth-clampthus far referred to being that commonly used in the Singer buttonhole machine.

In accordance with my invention I provide the clamp with two arms c c', having holes at their righthand ends, viewing Figs. 1 and 2. The end of the rock-shaft b is bored for 'the reception of a stud-screw c2, to form a pivot for said arm c. The rock-shaft?) has applied to it at its opposite end, between the ear a7 and the lever b', the other arm c. These arms c c are extended beyond the end of the base a of the usual cloth-clamp, and their outer ends are connected by a web c3, (see Fig. 4,) having a cam-slot 33 and screw-holes 2. The web c3 at each edge has secured to it in any usual way a gib c4, the said gibs being undercut at their inner edges to form a dovetailed space (see Fig. 5) for the reception of a slide d, the edges of which next the gibs are shaped to it between .the edges of the gibs. The gibs have holes 3 for the reception of screws 4, by which to attach to them a cover-plate d', having a slot 5, up through which projects a pin 6, carried by a switch block or dog'd2, adapted to turn on a pivot 10, held by the cap-plate and extended down below it. The pin 6 is acted upon by a spring 7, shown as held on the cap-plate by a screw 8, the spring 7 normally keeping the point of the switch in the position shown in Fig. 3.

The slide d has at its end next the but-tonhole to be stitched a jaw e, (shown best in Fig. 3,) it being shown as fixed. The slide d has a second jaw (shown as a lever e)'pivoted at 12 on the said slide and provided at its lefthand end, viewing Fig. 3, with a roller or other stud e2, a spring e3 normally acting to keep the short arm of the jaw e pressed against the jaw e to thus hold fast the needle-thread grasped between them. The jaws ce constitute one form of thread-clamp. The slide d has a stud 13 extended below it. (See Figs. 3 and 4, the stud in Fig. 4 being supposed to be a section.) This stud 13 serves as the fulorum for the thread-cutterf. (Shown by full lines, Fig. 4, by dotted lines, Fig. 3, and separately in Fig. 7.) This cutter has apin 14 extended down from its lower side into the slot 33, the cutting-edge 15 of the said cutter normally standing, while a button-hole is being stitched, close to the inner beveled edge of the thread-clamping jaw e.

The slide d has connected to it by screw 16 a bar 17, which is jointed at 18 to a link 19, pivoted at 2O on an upright 2l, erected on the stand b7, the said link 19 having, as shown, a slot 22, which is entered by a pin 23 of an arm 24, which I have added to the lever 25,which, except for said arm, is the same as in the usual cloth clamp referred to, the said arm 'at its left-hand end resting just below the head 26 of the pin bs, before referred to.

The arms c c are slotted to receive in them the pivot-pins which secure the clampingjaws be to the ends of the arms a3, so that as the said arms are lifted by the lever b to remove the cloth from the cloth-clamp the arms c c and their attached parts are also lifted to turn about the shaft b as a center.

Vhen the button-hole has been overstitched in the material clamped in the cloth-clamp, the operator stops the machine, and with his finger on the lever 25 depresses it to lift the pin bs preparatory to reversing the clamp or bringing it back into starting position to have its jaws opened and the material removed and put back again with another slitted portion of the material in place to be stitched. Now, as the operator depresses the lever 25 to raise the pin bs he also draws the slide d to the right, and in so doing the roller-stud e2 acts on the switch or dog d2, which causes the jaw e to be turned in the direction to carry its short end away from the stationary jaw e, the said open jaws acting as the thumb and iinger of the operator to cross and embrace the needle-thread between the work held in the cloth-clamp and the eye of the needle n, and as soon as the roll e2 passes the switch or dog the spring e3 acts to clamp the thread-clamping jaws on the needle-thread. As the slide d is moved forward, as described, the pin 14 of the thread-cutter f, acting in the slot 33, turns the thread-cutter on its pivot 13 and cuts the needle-thread off between the thread-clamp and the work held in the clamp. The thread-clamp holds the needle-thread as the cloth-clamp is reversed, and while the jaws of the cloth-clamp are opened for the removal of the work or its change of position therein, and while the cloth-clamp is closed the thread-clamp retaining the end of the needle-thread until after the stitching has been started for another buttonhole. The operator releases the lever 25 as soon as the clamp has been reversed, and the spring al, through the pin bs, turns the lever 25 inthe opposite direction, the slide d at such time being moved back into its normal position, Fig. 3; but in going back into such position the roller-stud e2 passes between the switch d2 and the gib next to it, the switch yielding and leaving the thread-clamp closed on the needle-thread. The thread-clamp, as herein shown, holds the needle-thread until the operator again depresses the lever 25; but it is not essential to hold the said thread after IOO IIO

one or two stitches, although it does no harm to hold it until the thread-clamp is to be again actuated to grasp the needle-thread at the completion of another button-hole.

' the needle-thread out or away from the clamp.

It will be obvious to one skilled in the art that the particular shapeof the thread-clamping jaws and the cutter may be modified Very considerably without departing from Vmy invention, and the devices employed for moving the thread-clamping jaws and cutter might be also varied very considerably in shape, according to the particular shape of the cloth-clamp holding the material to be overstitched, as it is well known that in some classes of button-hole-stitching machines the clamp does not rotate.

I have shown the slide carrying the threadclamping devices as moved by the lever 25. I have selected that part of the clamp herein shown as the actuating means for the slide or thread-clamp because that lever must be moved after the completion of each buttonhole, and when my invention is applied to any other usual form of cloth-clamp I shall select as the actuating device for the threadclamp to move it toward and to grasp the needle-thread, as described, between the needle and the clamp any part of the said clothclamp which always has to be moved in clamping and unclamping the material, the particular part or parts of such other Wellknown form of clamp or device co-operating therewith from which to derive movement for the thread-clamp, as described, being left to the judgment of the builder of the machine.

I claiml. A work or cloth clamp for a button-hole sewingmachine, provided with the usual clamping-jaws, said work-clamp having thereon a traveling thread-clamp adjacent to said jaws and being thus adapted to grasp and hold the needle-thread between the work held in said jaws and the needle.

2. A work or cloth clamp for abutton-hole sewing machine, provided with the usual clamping-jaws, said work-clamp having thereon a thread-clamp adjacent to said clampingjaws, combined with a thread-cutter arranged between the said thread-clamp and the point at which the material is held by the said clamping-jaws, whereby the needle-thread may be severed close to the work when abutton-hole is completed and then be held by the said thread-clamp while the work-clamp is reversed and until after the stitching of the subsequent button-hole is commenced.

3. A cloth-clamp and a slide, as cl, having thread-clamping devices, combined with devices to connect the said slide with a part of the cloth-clamp which is moved between the 'a cutter to cut the needle-thread, and actuating devices for the said cutter, substantially as described.

In testimony whereof I have signed my name to this speciiication in the presence of two subscribing witnesses.

EDW'ARD B. ALLEN.

Witnesses:

L. A. BENNETT, J. G. GREENE. 

